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arcmsr(4): Use MSI if it is supported by the device.
[dragonfly.git] / sys / netinet / ip_output.c
blob72678c857c843641a7d473dffd42e673024e58b6
1 /*
2 * Copyright (c) 1982, 1986, 1988, 1990, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94
30 * $FreeBSD: src/sys/netinet/ip_output.c,v 1.99.2.37 2003/04/15 06:44:45 silby Exp $
31 */
32
33 #define _IP_VHL
34
35 #include "opt_ipdn.h"
36 #include "opt_ipdivert.h"
37 #include "opt_ipsec.h"
38 #include "opt_mbuf_stress_test.h"
39 #include "opt_mpls.h"
40
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/kernel.h>
44 #include <sys/malloc.h>
45 #include <sys/mbuf.h>
46 #include <sys/protosw.h>
47 #include <sys/socket.h>
48 #include <sys/socketvar.h>
49 #include <sys/proc.h>
50 #include <sys/priv.h>
51 #include <sys/sysctl.h>
52 #include <sys/in_cksum.h>
53 #include <sys/lock.h>
54
55 #include <sys/thread2.h>
56 #include <sys/mplock2.h>
57 #include <sys/msgport2.h>
58
59 #include <net/if.h>
60 #include <net/netisr.h>
61 #include <net/pfil.h>
62 #include <net/route.h>
63
64 #include <netinet/in.h>
65 #include <netinet/in_systm.h>
66 #include <netinet/ip.h>
67 #include <netinet/in_pcb.h>
68 #include <netinet/in_var.h>
69 #include <netinet/ip_var.h>
70
71 #include <netproto/mpls/mpls_var.h>
72
73 static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "internet multicast options");
74
75 #ifdef IPSEC
76 #include <netinet6/ipsec.h>
77 #include <netproto/key/key.h>
78 #ifdef IPSEC_DEBUG
79 #include <netproto/key/key_debug.h>
80 #else
81 #define KEYDEBUG(lev,arg)
82 #endif
83 #endif /*IPSEC*/
84
85 #ifdef FAST_IPSEC
86 #include <netproto/ipsec/ipsec.h>
87 #include <netproto/ipsec/xform.h>
88 #include <netproto/ipsec/key.h>
89 #endif /*FAST_IPSEC*/
90
91 #include <net/ipfw/ip_fw.h>
92 #include <net/dummynet/ip_dummynet.h>
93
94 #define print_ip(x, a, y) kprintf("%s %d.%d.%d.%d%s",\
95 x, (ntohl(a.s_addr)>>24)&0xFF,\
96 (ntohl(a.s_addr)>>16)&0xFF,\
97 (ntohl(a.s_addr)>>8)&0xFF,\
98 (ntohl(a.s_addr))&0xFF, y);
99
100 u_short ip_id;
101
102 #ifdef MBUF_STRESS_TEST
103 int mbuf_frag_size = 0;
104 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW,
105 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size");
106 #endif
107
108 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *);
109 static struct ifnet *ip_multicast_if(struct in_addr *, int *);
110 static void ip_mloopback
111 (struct ifnet *, struct mbuf *, struct sockaddr_in *, int);
112 static int ip_getmoptions
113 (struct sockopt *, struct ip_moptions *);
114 static int ip_pcbopts(int, struct mbuf **, struct mbuf *);
115 static int ip_setmoptions
116 (struct sockopt *, struct ip_moptions **);
117
118 int ip_optcopy(struct ip *, struct ip *);
119
120 extern int route_assert_owner_access;
121
122 extern struct protosw inetsw[];
123
124 static int
125 ip_localforward(struct mbuf *m, const struct sockaddr_in *dst, int hlen)
126 {
127 struct in_ifaddr_container *iac;
128
129 /*
130 * We need to figure out if we have been forwarded to a local
131 * socket. If so, then we should somehow "loop back" to
132 * ip_input(), and get directed to the PCB as if we had received
133 * this packet. This is because it may be difficult to identify
134 * the packets you want to forward until they are being output
135 * and have selected an interface (e.g. locally initiated
136 * packets). If we used the loopback inteface, we would not be
137 * able to control what happens as the packet runs through
138 * ip_input() as it is done through a ISR.
139 */
140 LIST_FOREACH(iac, INADDR_HASH(dst->sin_addr.s_addr), ia_hash) {
141 /*
142 * If the addr to forward to is one of ours, we pretend
143 * to be the destination for this packet.
144 */
145 if (IA_SIN(iac->ia)->sin_addr.s_addr == dst->sin_addr.s_addr)
146 break;
147 }
148 if (iac != NULL) {
149 struct ip *ip;
150
151 if (m->m_pkthdr.rcvif == NULL)
152 m->m_pkthdr.rcvif = ifunit("lo0");
153 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
154 m->m_pkthdr.csum_flags |= CSUM_DATA_VALID |
155 CSUM_PSEUDO_HDR;
156 m->m_pkthdr.csum_data = 0xffff;
157 }
158 m->m_pkthdr.csum_flags |= CSUM_IP_CHECKED | CSUM_IP_VALID;
159
160 /*
161 * Make sure that the IP header is in one mbuf,
162 * required by ip_input
163 */
164 if (m->m_len < hlen) {
165 m = m_pullup(m, hlen);
166 if (m == NULL) {
167 /* The packet was freed; we are done */
168 return 1;
169 }
170 }
171 ip = mtod(m, struct ip *);
172
173 ip->ip_len = htons(ip->ip_len);
174 ip->ip_off = htons(ip->ip_off);
175 ip_input(m);
176
177 return 1; /* The packet gets forwarded locally */
178 }
179 return 0;
180 }
181
182 /*
183 * IP output. The packet in mbuf chain m contains a skeletal IP
184 * header (with len, off, ttl, proto, tos, src, dst).
185 * The mbuf chain containing the packet will be freed.
186 * The mbuf opt, if present, will not be freed.
187 */
188 int
189 ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro,
190 int flags, struct ip_moptions *imo, struct inpcb *inp)
191 {
192 struct ip *ip;
193 struct ifnet *ifp = NULL; /* keep compiler happy */
194 struct mbuf *m;
195 int hlen = sizeof(struct ip);
196 int len, error = 0;
197 struct sockaddr_in *dst = NULL; /* keep compiler happy */
198 struct in_ifaddr *ia = NULL;
199 int isbroadcast, sw_csum;
200 struct in_addr pkt_dst;
201 struct route iproute;
202 struct m_tag *mtag;
203 #ifdef IPSEC
204 struct secpolicy *sp = NULL;
205 struct socket *so = inp ? inp->inp_socket : NULL;
206 #endif
207 #ifdef FAST_IPSEC
208 struct secpolicy *sp = NULL;
209 struct tdb_ident *tdbi;
210 #endif /* FAST_IPSEC */
211 struct sockaddr_in *next_hop = NULL;
212 int src_was_INADDR_ANY = 0; /* as the name says... */
213
214 m = m0;
215 M_ASSERTPKTHDR(m);
216
217 if (ro == NULL) {
218 ro = &iproute;
219 bzero(ro, sizeof *ro);
220 } else if (ro->ro_rt != NULL && ro->ro_rt->rt_cpuid != mycpuid) {
221 if (flags & IP_DEBUGROUTE) {
222 if (route_assert_owner_access) {
223 panic("ip_output: "
224 "rt rt_cpuid %d accessed on cpu %d\n",
225 ro->ro_rt->rt_cpuid, mycpuid);
226 } else {
227 kprintf("ip_output: "
228 "rt rt_cpuid %d accessed on cpu %d\n",
229 ro->ro_rt->rt_cpuid, mycpuid);
230 print_backtrace(-1);
231 }
232 }
233
234 /*
235 * XXX
236 * If the cached rtentry's owner CPU is not the current CPU,
237 * then don't touch the cached rtentry (remote free is too
238 * expensive in this context); just relocate the route.
239 */
240 ro = &iproute;
241 bzero(ro, sizeof *ro);
242 }
243
244 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) {
245 /* Next hop */
246 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
247 KKASSERT(mtag != NULL);
248 next_hop = m_tag_data(mtag);
249 }
250
251 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
252 struct dn_pkt *dn_pkt;
253
254 /* Extract info from dummynet tag */
255 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
256 KKASSERT(mtag != NULL);
257 dn_pkt = m_tag_data(mtag);
258
259 /*
260 * The packet was already tagged, so part of the
261 * processing was already done, and we need to go down.
262 * Get the calculated parameters from the tag.
263 */
264 ifp = dn_pkt->ifp;
265
266 KKASSERT(ro == &iproute);
267 *ro = dn_pkt->ro; /* structure copy */
268 KKASSERT(ro->ro_rt == NULL || ro->ro_rt->rt_cpuid == mycpuid);
269
270 dst = dn_pkt->dn_dst;
271 if (dst == (struct sockaddr_in *)&(dn_pkt->ro.ro_dst)) {
272 /* If 'dst' points into dummynet tag, adjust it */
273 dst = (struct sockaddr_in *)&(ro->ro_dst);
274 }
275
276 ip = mtod(m, struct ip *);
277 hlen = IP_VHL_HL(ip->ip_vhl) << 2 ;
278 if (ro->ro_rt)
279 ia = ifatoia(ro->ro_rt->rt_ifa);
280 goto sendit;
281 }
282
283 if (opt) {
284 len = 0;
285 m = ip_insertoptions(m, opt, &len);
286 if (len != 0)
287 hlen = len;
288 }
289 ip = mtod(m, struct ip *);
290
291 /*
292 * Fill in IP header.
293 */
294 if (!(flags & (IP_FORWARDING|IP_RAWOUTPUT))) {
295 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, hlen >> 2);
296 ip->ip_off &= IP_DF;
297 ip->ip_id = ip_newid();
298 ipstat.ips_localout++;
299 } else {
300 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
301 }
302
303 reroute:
304 pkt_dst = next_hop ? next_hop->sin_addr : ip->ip_dst;
305
306 dst = (struct sockaddr_in *)&ro->ro_dst;
307 /*
308 * If there is a cached route,
309 * check that it is to the same destination
310 * and is still up. If not, free it and try again.
311 * The address family should also be checked in case of sharing the
312 * cache with IPv6.
313 */
314 if (ro->ro_rt &&
315 (!(ro->ro_rt->rt_flags & RTF_UP) ||
316 dst->sin_family != AF_INET ||
317 dst->sin_addr.s_addr != pkt_dst.s_addr)) {
318 rtfree(ro->ro_rt);
319 ro->ro_rt = NULL;
320 }
321 if (ro->ro_rt == NULL) {
322 bzero(dst, sizeof *dst);
323 dst->sin_family = AF_INET;
324 dst->sin_len = sizeof *dst;
325 dst->sin_addr = pkt_dst;
326 }
327 /*
328 * If routing to interface only,
329 * short circuit routing lookup.
330 */
331 if (flags & IP_ROUTETOIF) {
332 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL &&
333 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == NULL) {
334 ipstat.ips_noroute++;
335 error = ENETUNREACH;
336 goto bad;
337 }
338 ifp = ia->ia_ifp;
339 ip->ip_ttl = 1;
340 isbroadcast = in_broadcast(dst->sin_addr, ifp);
341 } else if (IN_MULTICAST(ntohl(pkt_dst.s_addr)) &&
342 imo != NULL && imo->imo_multicast_ifp != NULL) {
343 /*
344 * Bypass the normal routing lookup for multicast
345 * packets if the interface is specified.
346 */
347 ifp = imo->imo_multicast_ifp;
348 ia = IFP_TO_IA(ifp);
349 isbroadcast = 0; /* fool gcc */
350 } else {
351 /*
352 * If this is the case, we probably don't want to allocate
353 * a protocol-cloned route since we didn't get one from the
354 * ULP. This lets TCP do its thing, while not burdening
355 * forwarding or ICMP with the overhead of cloning a route.
356 * Of course, we still want to do any cloning requested by
357 * the link layer, as this is probably required in all cases
358 * for correct operation (as it is for ARP).
359 */
360 if (ro->ro_rt == NULL)
361 rtalloc_ign(ro, RTF_PRCLONING);
362 if (ro->ro_rt == NULL) {
363 ipstat.ips_noroute++;
364 error = EHOSTUNREACH;
365 goto bad;
366 }
367 ia = ifatoia(ro->ro_rt->rt_ifa);
368 ifp = ro->ro_rt->rt_ifp;
369 ro->ro_rt->rt_use++;
370 if (ro->ro_rt->rt_flags & RTF_GATEWAY)
371 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway;
372 if (ro->ro_rt->rt_flags & RTF_HOST)
373 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST);
374 else
375 isbroadcast = in_broadcast(dst->sin_addr, ifp);
376 }
377 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) {
378 struct in_multi *inm;
379
380 m->m_flags |= M_MCAST;
381 /*
382 * IP destination address is multicast. Make sure "dst"
383 * still points to the address in "ro". (It may have been
384 * changed to point to a gateway address, above.)
385 */
386 dst = (struct sockaddr_in *)&ro->ro_dst;
387 /*
388 * See if the caller provided any multicast options
389 */
390 if (imo != NULL) {
391 ip->ip_ttl = imo->imo_multicast_ttl;
392 if (imo->imo_multicast_vif != -1) {
393 ip->ip_src.s_addr =
394 ip_mcast_src ?
395 ip_mcast_src(imo->imo_multicast_vif) :
396 INADDR_ANY;
397 }
398 } else {
399 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
400 }
401 /*
402 * Confirm that the outgoing interface supports multicast.
403 */
404 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
405 if (!(ifp->if_flags & IFF_MULTICAST)) {
406 ipstat.ips_noroute++;
407 error = ENETUNREACH;
408 goto bad;
409 }
410 }
411 /*
412 * If source address not specified yet, use address
413 * of outgoing interface.
414 */
415 if (ip->ip_src.s_addr == INADDR_ANY) {
416 /* Interface may have no addresses. */
417 if (ia != NULL)
418 ip->ip_src = IA_SIN(ia)->sin_addr;
419 }
420
421 IN_LOOKUP_MULTI(pkt_dst, ifp, inm);
422 if (inm != NULL &&
423 (imo == NULL || imo->imo_multicast_loop)) {
424 /*
425 * If we belong to the destination multicast group
426 * on the outgoing interface, and the caller did not
427 * forbid loopback, loop back a copy.
428 */
429 ip_mloopback(ifp, m, dst, hlen);
430 } else {
431 /*
432 * If we are acting as a multicast router, perform
433 * multicast forwarding as if the packet had just
434 * arrived on the interface to which we are about
435 * to send. The multicast forwarding function
436 * recursively calls this function, using the
437 * IP_FORWARDING flag to prevent infinite recursion.
438 *
439 * Multicasts that are looped back by ip_mloopback(),
440 * above, will be forwarded by the ip_input() routine,
441 * if necessary.
442 */
443 if (ip_mrouter && !(flags & IP_FORWARDING)) {
444 /*
445 * If rsvp daemon is not running, do not
446 * set ip_moptions. This ensures that the packet
447 * is multicast and not just sent down one link
448 * as prescribed by rsvpd.
449 */
450 if (!rsvp_on)
451 imo = NULL;
452 if (ip_mforward) {
453 get_mplock();
454 if (ip_mforward(ip, ifp, m, imo) != 0) {
455 m_freem(m);
456 rel_mplock();
457 goto done;
458 }
459 rel_mplock();
460 }
461 }
462 }
463
464 /*
465 * Multicasts with a time-to-live of zero may be looped-
466 * back, above, but must not be transmitted on a network.
467 * Also, multicasts addressed to the loopback interface
468 * are not sent -- the above call to ip_mloopback() will
469 * loop back a copy if this host actually belongs to the
470 * destination group on the loopback interface.
471 */
472 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
473 m_freem(m);
474 goto done;
475 }
476
477 goto sendit;
478 } else {
479 m->m_flags &= ~M_MCAST;
480 }
481
482 /*
483 * If the source address is not specified yet, use the address
484 * of the outoing interface. In case, keep note we did that, so
485 * if the the firewall changes the next-hop causing the output
486 * interface to change, we can fix that.
487 */
488 if (ip->ip_src.s_addr == INADDR_ANY || src_was_INADDR_ANY) {
489 /* Interface may have no addresses. */
490 if (ia != NULL) {
491 ip->ip_src = IA_SIN(ia)->sin_addr;
492 src_was_INADDR_ANY = 1;
493 }
494 }
495
496 #ifdef ALTQ
497 /*
498 * Disable packet drop hack.
499 * Packetdrop should be done by queueing.
500 */
501 #else /* !ALTQ */
502 /*
503 * Verify that we have any chance at all of being able to queue
504 * the packet or packet fragments
505 */
506 if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >=
507 ifp->if_snd.ifq_maxlen) {
508 error = ENOBUFS;
509 ipstat.ips_odropped++;
510 goto bad;
511 }
512 #endif /* !ALTQ */
513
514 /*
515 * Look for broadcast address and
516 * verify user is allowed to send
517 * such a packet.
518 */
519 if (isbroadcast) {
520 if (!(ifp->if_flags & IFF_BROADCAST)) {
521 error = EADDRNOTAVAIL;
522 goto bad;
523 }
524 if (!(flags & IP_ALLOWBROADCAST)) {
525 error = EACCES;
526 goto bad;
527 }
528 /* don't allow broadcast messages to be fragmented */
529 if (ip->ip_len > ifp->if_mtu) {
530 error = EMSGSIZE;
531 goto bad;
532 }
533 m->m_flags |= M_BCAST;
534 } else {
535 m->m_flags &= ~M_BCAST;
536 }
537
538 sendit:
539 #ifdef IPSEC
540 /* get SP for this packet */
541 if (so == NULL)
542 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error);
543 else
544 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error);
545
546 if (sp == NULL) {
547 ipsecstat.out_inval++;
548 goto bad;
549 }
550
551 error = 0;
552
553 /* check policy */
554 switch (sp->policy) {
555 case IPSEC_POLICY_DISCARD:
556 /*
557 * This packet is just discarded.
558 */
559 ipsecstat.out_polvio++;
560 goto bad;
561
562 case IPSEC_POLICY_BYPASS:
563 case IPSEC_POLICY_NONE:
564 case IPSEC_POLICY_TCP:
565 /* no need to do IPsec. */
566 goto skip_ipsec;
567
568 case IPSEC_POLICY_IPSEC:
569 if (sp->req == NULL) {
570 /* acquire a policy */
571 error = key_spdacquire(sp);
572 goto bad;
573 }
574 break;
575
576 case IPSEC_POLICY_ENTRUST:
577 default:
578 kprintf("ip_output: Invalid policy found. %d\n", sp->policy);
579 }
580 {
581 struct ipsec_output_state state;
582 bzero(&state, sizeof state);
583 state.m = m;
584 if (flags & IP_ROUTETOIF) {
585 state.ro = &iproute;
586 bzero(&iproute, sizeof iproute);
587 } else
588 state.ro = ro;
589 state.dst = (struct sockaddr *)dst;
590
591 ip->ip_sum = 0;
592
593 /*
594 * XXX
595 * delayed checksums are not currently compatible with IPsec
596 */
597 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
598 in_delayed_cksum(m);
599 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
600 }
601
602 ip->ip_len = htons(ip->ip_len);
603 ip->ip_off = htons(ip->ip_off);
604
605 error = ipsec4_output(&state, sp, flags);
606
607 m = state.m;
608 if (flags & IP_ROUTETOIF) {
609 /*
610 * if we have tunnel mode SA, we may need to ignore
611 * IP_ROUTETOIF.
612 */
613 if (state.ro != &iproute || state.ro->ro_rt != NULL) {
614 flags &= ~IP_ROUTETOIF;
615 ro = state.ro;
616 }
617 } else
618 ro = state.ro;
619 dst = (struct sockaddr_in *)state.dst;
620 if (error) {
621 /* mbuf is already reclaimed in ipsec4_output. */
622 m0 = NULL;
623 switch (error) {
624 case EHOSTUNREACH:
625 case ENETUNREACH:
626 case EMSGSIZE:
627 case ENOBUFS:
628 case ENOMEM:
629 break;
630 default:
631 kprintf("ip4_output (ipsec): error code %d\n", error);
632 /*fall through*/
633 case ENOENT:
634 /* don't show these error codes to the user */
635 error = 0;
636 break;
637 }
638 goto bad;
639 }
640 }
641
642 /* be sure to update variables that are affected by ipsec4_output() */
643 ip = mtod(m, struct ip *);
644 #ifdef _IP_VHL
645 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
646 #else
647 hlen = ip->ip_hl << 2;
648 #endif
649 if (ro->ro_rt == NULL) {
650 if (!(flags & IP_ROUTETOIF)) {
651 kprintf("ip_output: "
652 "can't update route after IPsec processing\n");
653 error = EHOSTUNREACH; /*XXX*/
654 goto bad;
655 }
656 } else {
657 ia = ifatoia(ro->ro_rt->rt_ifa);
658 ifp = ro->ro_rt->rt_ifp;
659 }
660
661 /* make it flipped, again. */
662 ip->ip_len = ntohs(ip->ip_len);
663 ip->ip_off = ntohs(ip->ip_off);
664 skip_ipsec:
665 #endif /*IPSEC*/
666 #ifdef FAST_IPSEC
667 /*
668 * Check the security policy (SP) for the packet and, if
669 * required, do IPsec-related processing. There are two
670 * cases here; the first time a packet is sent through
671 * it will be untagged and handled by ipsec4_checkpolicy.
672 * If the packet is resubmitted to ip_output (e.g. after
673 * AH, ESP, etc. processing), there will be a tag to bypass
674 * the lookup and related policy checking.
675 */
676 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL);
677 crit_enter();
678 if (mtag != NULL) {
679 tdbi = (struct tdb_ident *)m_tag_data(mtag);
680 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND);
681 if (sp == NULL)
682 error = -EINVAL; /* force silent drop */
683 m_tag_delete(m, mtag);
684 } else {
685 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags,
686 &error, inp);
687 }
688 /*
689 * There are four return cases:
690 * sp != NULL apply IPsec policy
691 * sp == NULL, error == 0 no IPsec handling needed
692 * sp == NULL, error == -EINVAL discard packet w/o error
693 * sp == NULL, error != 0 discard packet, report error
694 */
695 if (sp != NULL) {
696 /* Loop detection, check if ipsec processing already done */
697 KASSERT(sp->req != NULL, ("ip_output: no ipsec request"));
698 for (mtag = m_tag_first(m); mtag != NULL;
699 mtag = m_tag_next(m, mtag)) {
700 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT)
701 continue;
702 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE &&
703 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED)
704 continue;
705 /*
706 * Check if policy has an SA associated with it.
707 * This can happen when an SP has yet to acquire
708 * an SA; e.g. on first reference. If it occurs,
709 * then we let ipsec4_process_packet do its thing.
710 */
711 if (sp->req->sav == NULL)
712 break;
713 tdbi = (struct tdb_ident *)m_tag_data(mtag);
714 if (tdbi->spi == sp->req->sav->spi &&
715 tdbi->proto == sp->req->sav->sah->saidx.proto &&
716 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst,
717 sizeof(union sockaddr_union)) == 0) {
718 /*
719 * No IPsec processing is needed, free
720 * reference to SP.
721 *
722 * NB: null pointer to avoid free at
723 * done: below.
724 */
725 KEY_FREESP(&sp), sp = NULL;
726 crit_exit();
727 goto spd_done;
728 }
729 }
730
731 /*
732 * Do delayed checksums now because we send before
733 * this is done in the normal processing path.
734 */
735 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
736 in_delayed_cksum(m);
737 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
738 }
739
740 ip->ip_len = htons(ip->ip_len);
741 ip->ip_off = htons(ip->ip_off);
742
743 /* NB: callee frees mbuf */
744 error = ipsec4_process_packet(m, sp->req, flags, 0);
745 /*
746 * Preserve KAME behaviour: ENOENT can be returned
747 * when an SA acquire is in progress. Don't propagate
748 * this to user-level; it confuses applications.
749 *
750 * XXX this will go away when the SADB is redone.
751 */
752 if (error == ENOENT)
753 error = 0;
754 crit_exit();
755 goto done;
756 } else {
757 crit_exit();
758
759 if (error != 0) {
760 /*
761 * Hack: -EINVAL is used to signal that a packet
762 * should be silently discarded. This is typically
763 * because we asked key management for an SA and
764 * it was delayed (e.g. kicked up to IKE).
765 */
766 if (error == -EINVAL)
767 error = 0;
768 goto bad;
769 } else {
770 /* No IPsec processing for this packet. */
771 }
772 #ifdef notyet
773 /*
774 * If deferred crypto processing is needed, check that
775 * the interface supports it.
776 */
777 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL);
778 if (mtag != NULL && !(ifp->if_capenable & IFCAP_IPSEC)) {
779 /* notify IPsec to do its own crypto */
780 ipsp_skipcrypto_unmark((struct tdb_ident *)m_tag_data(mtag));
781 error = EHOSTUNREACH;
782 goto bad;
783 }
784 #endif
785 }
786 spd_done:
787 #endif /* FAST_IPSEC */
788
789 /* We are already being fwd'd from a firewall. */
790 if (next_hop != NULL)
791 goto pass;
792
793 /* No pfil hooks */
794 if (!pfil_has_hooks(&inet_pfil_hook)) {
795 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
796 /*
797 * Strip dummynet tags from stranded packets
798 */
799 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
800 KKASSERT(mtag != NULL);
801 m_tag_delete(m, mtag);
802 m->m_pkthdr.fw_flags &= ~DUMMYNET_MBUF_TAGGED;
803 }
804 goto pass;
805 }
806
807 /*
808 * IpHack's section.
809 * - Xlate: translate packet's addr/port (NAT).
810 * - Firewall: deny/allow/etc.
811 * - Wrap: fake packet's addr/port <unimpl.>
812 * - Encapsulate: put it in another IP and send out. <unimp.>
813 */
814
815 /*
816 * Run through list of hooks for output packets.
817 */
818 error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT);
819 if (error != 0 || m == NULL)
820 goto done;
821 ip = mtod(m, struct ip *);
822
823 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) {
824 /*
825 * Check dst to make sure it is directly reachable on the
826 * interface we previously thought it was.
827 * If it isn't (which may be likely in some situations) we have
828 * to re-route it (ie, find a route for the next-hop and the
829 * associated interface) and set them here. This is nested
830 * forwarding which in most cases is undesirable, except where
831 * such control is nigh impossible. So we do it here.
832 * And I'm babbling.
833 */
834 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
835 KKASSERT(mtag != NULL);
836 next_hop = m_tag_data(mtag);
837
838 /*
839 * Try local forwarding first
840 */
841 if (ip_localforward(m, next_hop, hlen))
842 goto done;
843
844 /*
845 * Relocate the route based on next_hop.
846 * If the current route is inp's cache, keep it untouched.
847 */
848 if (ro == &iproute && ro->ro_rt != NULL) {
849 RTFREE(ro->ro_rt);
850 ro->ro_rt = NULL;
851 }
852 ro = &iproute;
853 bzero(ro, sizeof *ro);
854
855 /*
856 * Forwarding to broadcast address is not allowed.
857 * XXX Should we follow IP_ROUTETOIF?
858 */
859 flags &= ~(IP_ALLOWBROADCAST | IP_ROUTETOIF);
860
861 /* We are doing forwarding now */
862 flags |= IP_FORWARDING;
863
864 goto reroute;
865 }
866
867 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
868 struct dn_pkt *dn_pkt;
869
870 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
871 KKASSERT(mtag != NULL);
872 dn_pkt = m_tag_data(mtag);
873
874 /*
875 * Under certain cases it is not possible to recalculate
876 * 'ro' and 'dst', let alone 'flags', so just save them in
877 * dummynet tag and avoid the possible wrong reculcalation
878 * when we come back to ip_output() again.
879 *
880 * All other parameters have been already used and so they
881 * are not needed anymore.
882 * XXX if the ifp is deleted while a pkt is in dummynet,
883 * we are in trouble! (TODO use ifnet_detach_event)
884 *
885 * We need to copy *ro because for ICMP pkts (and maybe
886 * others) the caller passed a pointer into the stack;
887 * dst might also be a pointer into *ro so it needs to
888 * be updated.
889 */
890 dn_pkt->ro = *ro;
891 if (ro->ro_rt)
892 ro->ro_rt->rt_refcnt++;
893 if (dst == (struct sockaddr_in *)&ro->ro_dst) {
894 /* 'dst' points into 'ro' */
895 dst = (struct sockaddr_in *)&(dn_pkt->ro.ro_dst);
896 }
897 dn_pkt->dn_dst = dst;
898 dn_pkt->flags = flags;
899
900 ip_dn_queue(m);
901 goto done;
902 }
903 pass:
904 /* 127/8 must not appear on wire - RFC1122. */
905 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
906 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
907 if (!(ifp->if_flags & IFF_LOOPBACK)) {
908 ipstat.ips_badaddr++;
909 error = EADDRNOTAVAIL;
910 goto bad;
911 }
912 }
913
914 m->m_pkthdr.csum_flags |= CSUM_IP;
915 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist;
916 if (sw_csum & CSUM_DELAY_DATA) {
917 in_delayed_cksum(m);
918 sw_csum &= ~CSUM_DELAY_DATA;
919 }
920 m->m_pkthdr.csum_flags &= ifp->if_hwassist;
921
922 /*
923 * If small enough for interface, or the interface will take
924 * care of the fragmentation for us, can just send directly.
925 */
926 if (ip->ip_len <= ifp->if_mtu || ((ifp->if_hwassist & CSUM_FRAGMENT) &&
927 !(ip->ip_off & IP_DF))) {
928 ip->ip_len = htons(ip->ip_len);
929 ip->ip_off = htons(ip->ip_off);
930 ip->ip_sum = 0;
931 if (sw_csum & CSUM_DELAY_IP) {
932 if (ip->ip_vhl == IP_VHL_BORING)
933 ip->ip_sum = in_cksum_hdr(ip);
934 else
935 ip->ip_sum = in_cksum(m, hlen);
936 }
937
938 /* Record statistics for this interface address. */
939 if (!(flags & IP_FORWARDING) && ia) {
940 ia->ia_ifa.if_opackets++;
941 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
942 }
943
944 #ifdef IPSEC
945 /* clean ipsec history once it goes out of the node */
946 ipsec_delaux(m);
947 #endif
948
949 #ifdef MBUF_STRESS_TEST
950 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) {
951 struct mbuf *m1, *m2;
952 int length, tmp;
953
954 tmp = length = m->m_pkthdr.len;
955
956 while ((length -= mbuf_frag_size) >= 1) {
957 m1 = m_split(m, length, MB_DONTWAIT);
958 if (m1 == NULL)
959 break;
960 m2 = m;
961 while (m2->m_next != NULL)
962 m2 = m2->m_next;
963 m2->m_next = m1;
964 }
965 m->m_pkthdr.len = tmp;
966 }
967 #endif
968
969 #ifdef MPLS
970 if (!mpls_output_process(m, ro->ro_rt))
971 goto done;
972 #endif
973 error = ifp->if_output(ifp, m, (struct sockaddr *)dst,
974 ro->ro_rt);
975 goto done;
976 }
977
978 if (ip->ip_off & IP_DF) {
979 error = EMSGSIZE;
980 /*
981 * This case can happen if the user changed the MTU
982 * of an interface after enabling IP on it. Because
983 * most netifs don't keep track of routes pointing to
984 * them, there is no way for one to update all its
985 * routes when the MTU is changed.
986 */
987 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) &&
988 !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) &&
989 (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) {
990 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu;
991 }
992 ipstat.ips_cantfrag++;
993 goto bad;
994 }
995
996 /*
997 * Too large for interface; fragment if possible. If successful,
998 * on return, m will point to a list of packets to be sent.
999 */
1000 error = ip_fragment(ip, &m, ifp->if_mtu, ifp->if_hwassist, sw_csum);
1001 if (error)
1002 goto bad;
1003 for (; m; m = m0) {
1004 m0 = m->m_nextpkt;
1005 m->m_nextpkt = NULL;
1006 #ifdef IPSEC
1007 /* clean ipsec history once it goes out of the node */
1008 ipsec_delaux(m);
1009 #endif
1010 if (error == 0) {
1011 /* Record statistics for this interface address. */
1012 if (ia != NULL) {
1013 ia->ia_ifa.if_opackets++;
1014 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
1015 }
1016 #ifdef MPLS
1017 if (!mpls_output_process(m, ro->ro_rt))
1018 continue;
1019 #endif
1020 error = ifp->if_output(ifp, m, (struct sockaddr *)dst,
1021 ro->ro_rt);
1022 } else {
1023 m_freem(m);
1024 }
1025 }
1026
1027 if (error == 0)
1028 ipstat.ips_fragmented++;
1029
1030 done:
1031 if (ro == &iproute && ro->ro_rt != NULL) {
1032 RTFREE(ro->ro_rt);
1033 ro->ro_rt = NULL;
1034 }
1035 #ifdef IPSEC
1036 if (sp != NULL) {
1037 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
1038 kprintf("DP ip_output call free SP:%p\n", sp));
1039 key_freesp(sp);
1040 }
1041 #endif
1042 #ifdef FAST_IPSEC
1043 if (sp != NULL)
1044 KEY_FREESP(&sp);
1045 #endif
1046 return (error);
1047 bad:
1048 m_freem(m);
1049 goto done;
1050 }
1051
1052 /*
1053 * Create a chain of fragments which fit the given mtu. m_frag points to the
1054 * mbuf to be fragmented; on return it points to the chain with the fragments.
1055 * Return 0 if no error. If error, m_frag may contain a partially built
1056 * chain of fragments that should be freed by the caller.
1057 *
1058 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
1059 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP).
1060 */
1061 int
1062 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
1063 u_long if_hwassist_flags, int sw_csum)
1064 {
1065 int error = 0;
1066 int hlen = IP_VHL_HL(ip->ip_vhl) << 2;
1067 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */
1068 int off;
1069 struct mbuf *m0 = *m_frag; /* the original packet */
1070 int firstlen;
1071 struct mbuf **mnext;
1072 int nfrags;
1073
1074 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */
1075 ipstat.ips_cantfrag++;
1076 return EMSGSIZE;
1077 }
1078
1079 /*
1080 * Must be able to put at least 8 bytes per fragment.
1081 */
1082 if (len < 8)
1083 return EMSGSIZE;
1084
1085 /*
1086 * If the interface will not calculate checksums on
1087 * fragmented packets, then do it here.
1088 */
1089 if ((m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) &&
1090 !(if_hwassist_flags & CSUM_IP_FRAGS)) {
1091 in_delayed_cksum(m0);
1092 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1093 }
1094
1095 if (len > PAGE_SIZE) {
1096 /*
1097 * Fragment large datagrams such that each segment
1098 * contains a multiple of PAGE_SIZE amount of data,
1099 * plus headers. This enables a receiver to perform
1100 * page-flipping zero-copy optimizations.
1101 *
1102 * XXX When does this help given that sender and receiver
1103 * could have different page sizes, and also mtu could
1104 * be less than the receiver's page size ?
1105 */
1106 int newlen;
1107 struct mbuf *m;
1108
1109 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next)
1110 off += m->m_len;
1111
1112 /*
1113 * firstlen (off - hlen) must be aligned on an
1114 * 8-byte boundary
1115 */
1116 if (off < hlen)
1117 goto smart_frag_failure;
1118 off = ((off - hlen) & ~7) + hlen;
1119 newlen = (~PAGE_MASK) & mtu;
1120 if ((newlen + sizeof(struct ip)) > mtu) {
1121 /* we failed, go back the default */
1122 smart_frag_failure:
1123 newlen = len;
1124 off = hlen + len;
1125 }
1126 len = newlen;
1127
1128 } else {
1129 off = hlen + len;
1130 }
1131
1132 firstlen = off - hlen;
1133 mnext = &m0->m_nextpkt; /* pointer to next packet */
1134
1135 /*
1136 * Loop through length of segment after first fragment,
1137 * make new header and copy data of each part and link onto chain.
1138 * Here, m0 is the original packet, m is the fragment being created.
1139 * The fragments are linked off the m_nextpkt of the original
1140 * packet, which after processing serves as the first fragment.
1141 */
1142 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) {
1143 struct ip *mhip; /* ip header on the fragment */
1144 struct mbuf *m;
1145 int mhlen = sizeof(struct ip);
1146
1147 MGETHDR(m, MB_DONTWAIT, MT_HEADER);
1148 if (m == NULL) {
1149 error = ENOBUFS;
1150 ipstat.ips_odropped++;
1151 goto done;
1152 }
1153 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG;
1154 /*
1155 * In the first mbuf, leave room for the link header, then
1156 * copy the original IP header including options. The payload
1157 * goes into an additional mbuf chain returned by m_copy().
1158 */
1159 m->m_data += max_linkhdr;
1160 mhip = mtod(m, struct ip *);
1161 *mhip = *ip;
1162 if (hlen > sizeof(struct ip)) {
1163 mhlen = ip_optcopy(ip, mhip) + sizeof(struct ip);
1164 mhip->ip_vhl = IP_MAKE_VHL(IPVERSION, mhlen >> 2);
1165 }
1166 m->m_len = mhlen;
1167 /* XXX do we need to add ip->ip_off below ? */
1168 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off;
1169 if (off + len >= ip->ip_len) { /* last fragment */
1170 len = ip->ip_len - off;
1171 m->m_flags |= M_LASTFRAG;
1172 } else
1173 mhip->ip_off |= IP_MF;
1174 mhip->ip_len = htons((u_short)(len + mhlen));
1175 m->m_next = m_copy(m0, off, len);
1176 if (m->m_next == NULL) { /* copy failed */
1177 m_free(m);
1178 error = ENOBUFS; /* ??? */
1179 ipstat.ips_odropped++;
1180 goto done;
1181 }
1182 m->m_pkthdr.len = mhlen + len;
1183 m->m_pkthdr.rcvif = NULL;
1184 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags;
1185 mhip->ip_off = htons(mhip->ip_off);
1186 mhip->ip_sum = 0;
1187 if (sw_csum & CSUM_DELAY_IP)
1188 mhip->ip_sum = in_cksum(m, mhlen);
1189 *mnext = m;
1190 mnext = &m->m_nextpkt;
1191 }
1192 ipstat.ips_ofragments += nfrags;
1193
1194 /* set first marker for fragment chain */
1195 m0->m_flags |= M_FIRSTFRAG | M_FRAG;
1196 m0->m_pkthdr.csum_data = nfrags;
1197
1198 /*
1199 * Update first fragment by trimming what's been copied out
1200 * and updating header.
1201 */
1202 m_adj(m0, hlen + firstlen - ip->ip_len);
1203 m0->m_pkthdr.len = hlen + firstlen;
1204 ip->ip_len = htons((u_short)m0->m_pkthdr.len);
1205 ip->ip_off |= IP_MF;
1206 ip->ip_off = htons(ip->ip_off);
1207 ip->ip_sum = 0;
1208 if (sw_csum & CSUM_DELAY_IP)
1209 ip->ip_sum = in_cksum(m0, hlen);
1210
1211 done:
1212 *m_frag = m0;
1213 return error;
1214 }
1215
1216 void
1217 in_delayed_cksum(struct mbuf *m)
1218 {
1219 struct ip *ip;
1220 u_short csum, offset;
1221
1222 ip = mtod(m, struct ip *);
1223 offset = IP_VHL_HL(ip->ip_vhl) << 2 ;
1224 csum = in_cksum_skip(m, ip->ip_len, offset);
1225 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0)
1226 csum = 0xffff;
1227 offset += m->m_pkthdr.csum_data; /* checksum offset */
1228
1229 if (offset + sizeof(u_short) > m->m_len) {
1230 kprintf("delayed m_pullup, m->len: %d off: %d p: %d\n",
1231 m->m_len, offset, ip->ip_p);
1232 /*
1233 * XXX
1234 * this shouldn't happen, but if it does, the
1235 * correct behavior may be to insert the checksum
1236 * in the existing chain instead of rearranging it.
1237 */
1238 m = m_pullup(m, offset + sizeof(u_short));
1239 }
1240 *(u_short *)(m->m_data + offset) = csum;
1241 }
1242
1243 /*
1244 * Insert IP options into preformed packet.
1245 * Adjust IP destination as required for IP source routing,
1246 * as indicated by a non-zero in_addr at the start of the options.
1247 *
1248 * XXX This routine assumes that the packet has no options in place.
1249 */
1250 static struct mbuf *
1251 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen)
1252 {
1253 struct ipoption *p = mtod(opt, struct ipoption *);
1254 struct mbuf *n;
1255 struct ip *ip = mtod(m, struct ip *);
1256 unsigned optlen;
1257
1258 optlen = opt->m_len - sizeof p->ipopt_dst;
1259 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) {
1260 *phlen = 0;
1261 return (m); /* XXX should fail */
1262 }
1263 if (p->ipopt_dst.s_addr)
1264 ip->ip_dst = p->ipopt_dst;
1265 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) {
1266 MGETHDR(n, MB_DONTWAIT, MT_HEADER);
1267 if (n == NULL) {
1268 *phlen = 0;
1269 return (m);
1270 }
1271 n->m_pkthdr.rcvif = NULL;
1272 n->m_pkthdr.len = m->m_pkthdr.len + optlen;
1273 m->m_len -= sizeof(struct ip);
1274 m->m_data += sizeof(struct ip);
1275 n->m_next = m;
1276 m = n;
1277 m->m_len = optlen + sizeof(struct ip);
1278 m->m_data += max_linkhdr;
1279 memcpy(mtod(m, void *), ip, sizeof(struct ip));
1280 } else {
1281 m->m_data -= optlen;
1282 m->m_len += optlen;
1283 m->m_pkthdr.len += optlen;
1284 ovbcopy(ip, mtod(m, caddr_t), sizeof(struct ip));
1285 }
1286 ip = mtod(m, struct ip *);
1287 bcopy(p->ipopt_list, ip + 1, optlen);
1288 *phlen = sizeof(struct ip) + optlen;
1289 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, *phlen >> 2);
1290 ip->ip_len += optlen;
1291 return (m);
1292 }
1293
1294 /*
1295 * Copy options from ip to jp,
1296 * omitting those not copied during fragmentation.
1297 */
1298 int
1299 ip_optcopy(struct ip *ip, struct ip *jp)
1300 {
1301 u_char *cp, *dp;
1302 int opt, optlen, cnt;
1303
1304 cp = (u_char *)(ip + 1);
1305 dp = (u_char *)(jp + 1);
1306 cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip);
1307 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1308 opt = cp[0];
1309 if (opt == IPOPT_EOL)
1310 break;
1311 if (opt == IPOPT_NOP) {
1312 /* Preserve for IP mcast tunnel's LSRR alignment. */
1313 *dp++ = IPOPT_NOP;
1314 optlen = 1;
1315 continue;
1316 }
1317
1318 KASSERT(cnt >= IPOPT_OLEN + sizeof *cp,
1319 ("ip_optcopy: malformed ipv4 option"));
1320 optlen = cp[IPOPT_OLEN];
1321 KASSERT(optlen >= IPOPT_OLEN + sizeof *cp && optlen <= cnt,
1322 ("ip_optcopy: malformed ipv4 option"));
1323
1324 /* bogus lengths should have been caught by ip_dooptions */
1325 if (optlen > cnt)
1326 optlen = cnt;
1327 if (IPOPT_COPIED(opt)) {
1328 bcopy(cp, dp, optlen);
1329 dp += optlen;
1330 }
1331 }
1332 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++)
1333 *dp++ = IPOPT_EOL;
1334 return (optlen);
1335 }
1336
1337 /*
1338 * IP socket option processing.
1339 */
1340 void
1341 ip_ctloutput(netmsg_t msg)
1342 {
1343 struct socket *so = msg->base.nm_so;
1344 struct sockopt *sopt = msg->ctloutput.nm_sopt;
1345 struct inpcb *inp = so->so_pcb;
1346 int error, optval;
1347
1348 error = optval = 0;
1349 if (sopt->sopt_level != IPPROTO_IP) {
1350 error = EINVAL;
1351 goto done;
1352 }
1353
1354 switch (sopt->sopt_dir) {
1355 case SOPT_SET:
1356 switch (sopt->sopt_name) {
1357 case IP_OPTIONS:
1358 #ifdef notyet
1359 case IP_RETOPTS:
1360 #endif
1361 {
1362 struct mbuf *m;
1363 if (sopt->sopt_valsize > MLEN) {
1364 error = EMSGSIZE;
1365 break;
1366 }
1367 MGET(m, sopt->sopt_td ? MB_WAIT : MB_DONTWAIT, MT_HEADER);
1368 if (m == NULL) {
1369 error = ENOBUFS;
1370 break;
1371 }
1372 m->m_len = sopt->sopt_valsize;
1373 error = soopt_to_kbuf(sopt, mtod(m, void *), m->m_len,
1374 m->m_len);
1375 error = ip_pcbopts(sopt->sopt_name,
1376 &inp->inp_options, m);
1377 goto done;
1378 }
1379
1380 case IP_TOS:
1381 case IP_TTL:
1382 case IP_MINTTL:
1383 case IP_RECVOPTS:
1384 case IP_RECVRETOPTS:
1385 case IP_RECVDSTADDR:
1386 case IP_RECVIF:
1387 case IP_RECVTTL:
1388 case IP_FAITH:
1389 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1390 sizeof optval);
1391 if (error)
1392 break;
1393 switch (sopt->sopt_name) {
1394 case IP_TOS:
1395 inp->inp_ip_tos = optval;
1396 break;
1397
1398 case IP_TTL:
1399 inp->inp_ip_ttl = optval;
1400 break;
1401 case IP_MINTTL:
1402 if (optval >= 0 && optval <= MAXTTL)
1403 inp->inp_ip_minttl = optval;
1404 else
1405 error = EINVAL;
1406 break;
1407 #define OPTSET(bit) \
1408 if (optval) \
1409 inp->inp_flags |= bit; \
1410 else \
1411 inp->inp_flags &= ~bit;
1412
1413 case IP_RECVOPTS:
1414 OPTSET(INP_RECVOPTS);
1415 break;
1416
1417 case IP_RECVRETOPTS:
1418 OPTSET(INP_RECVRETOPTS);
1419 break;
1420
1421 case IP_RECVDSTADDR:
1422 OPTSET(INP_RECVDSTADDR);
1423 break;
1424
1425 case IP_RECVIF:
1426 OPTSET(INP_RECVIF);
1427 break;
1428
1429 case IP_RECVTTL:
1430 OPTSET(INP_RECVTTL);
1431 break;
1432
1433 case IP_FAITH:
1434 OPTSET(INP_FAITH);
1435 break;
1436 }
1437 break;
1438 #undef OPTSET
1439
1440 case IP_MULTICAST_IF:
1441 case IP_MULTICAST_VIF:
1442 case IP_MULTICAST_TTL:
1443 case IP_MULTICAST_LOOP:
1444 case IP_ADD_MEMBERSHIP:
1445 case IP_DROP_MEMBERSHIP:
1446 error = ip_setmoptions(sopt, &inp->inp_moptions);
1447 break;
1448
1449 case IP_PORTRANGE:
1450 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1451 sizeof optval);
1452 if (error)
1453 break;
1454
1455 switch (optval) {
1456 case IP_PORTRANGE_DEFAULT:
1457 inp->inp_flags &= ~(INP_LOWPORT);
1458 inp->inp_flags &= ~(INP_HIGHPORT);
1459 break;
1460
1461 case IP_PORTRANGE_HIGH:
1462 inp->inp_flags &= ~(INP_LOWPORT);
1463 inp->inp_flags |= INP_HIGHPORT;
1464 break;
1465
1466 case IP_PORTRANGE_LOW:
1467 inp->inp_flags &= ~(INP_HIGHPORT);
1468 inp->inp_flags |= INP_LOWPORT;
1469 break;
1470
1471 default:
1472 error = EINVAL;
1473 break;
1474 }
1475 break;
1476
1477 #if defined(IPSEC) || defined(FAST_IPSEC)
1478 case IP_IPSEC_POLICY:
1479 {
1480 caddr_t req;
1481 size_t len = 0;
1482 int priv;
1483 struct mbuf *m;
1484 int optname;
1485
1486 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1487 break;
1488 soopt_to_mbuf(sopt, m);
1489 priv = (sopt->sopt_td != NULL &&
1490 priv_check(sopt->sopt_td, PRIV_ROOT) != 0) ? 0 : 1;
1491 req = mtod(m, caddr_t);
1492 len = m->m_len;
1493 optname = sopt->sopt_name;
1494 error = ipsec4_set_policy(inp, optname, req, len, priv);
1495 m_freem(m);
1496 break;
1497 }
1498 #endif /*IPSEC*/
1499
1500 default:
1501 error = ENOPROTOOPT;
1502 break;
1503 }
1504 break;
1505
1506 case SOPT_GET:
1507 switch (sopt->sopt_name) {
1508 case IP_OPTIONS:
1509 case IP_RETOPTS:
1510 if (inp->inp_options)
1511 soopt_from_kbuf(sopt, mtod(inp->inp_options,
1512 char *),
1513 inp->inp_options->m_len);
1514 else
1515 sopt->sopt_valsize = 0;
1516 break;
1517
1518 case IP_TOS:
1519 case IP_TTL:
1520 case IP_MINTTL:
1521 case IP_RECVOPTS:
1522 case IP_RECVRETOPTS:
1523 case IP_RECVDSTADDR:
1524 case IP_RECVTTL:
1525 case IP_RECVIF:
1526 case IP_PORTRANGE:
1527 case IP_FAITH:
1528 switch (sopt->sopt_name) {
1529
1530 case IP_TOS:
1531 optval = inp->inp_ip_tos;
1532 break;
1533
1534 case IP_TTL:
1535 optval = inp->inp_ip_ttl;
1536 break;
1537 case IP_MINTTL:
1538 optval = inp->inp_ip_minttl;
1539 break;
1540
1541 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0)
1542
1543 case IP_RECVOPTS:
1544 optval = OPTBIT(INP_RECVOPTS);
1545 break;
1546
1547 case IP_RECVRETOPTS:
1548 optval = OPTBIT(INP_RECVRETOPTS);
1549 break;
1550
1551 case IP_RECVDSTADDR:
1552 optval = OPTBIT(INP_RECVDSTADDR);
1553 break;
1554
1555 case IP_RECVTTL:
1556 optval = OPTBIT(INP_RECVTTL);
1557 break;
1558
1559 case IP_RECVIF:
1560 optval = OPTBIT(INP_RECVIF);
1561 break;
1562
1563 case IP_PORTRANGE:
1564 if (inp->inp_flags & INP_HIGHPORT)
1565 optval = IP_PORTRANGE_HIGH;
1566 else if (inp->inp_flags & INP_LOWPORT)
1567 optval = IP_PORTRANGE_LOW;
1568 else
1569 optval = 0;
1570 break;
1571
1572 case IP_FAITH:
1573 optval = OPTBIT(INP_FAITH);
1574 break;
1575 }
1576 soopt_from_kbuf(sopt, &optval, sizeof optval);
1577 break;
1578
1579 case IP_MULTICAST_IF:
1580 case IP_MULTICAST_VIF:
1581 case IP_MULTICAST_TTL:
1582 case IP_MULTICAST_LOOP:
1583 case IP_ADD_MEMBERSHIP:
1584 case IP_DROP_MEMBERSHIP:
1585 error = ip_getmoptions(sopt, inp->inp_moptions);
1586 break;
1587
1588 #if defined(IPSEC) || defined(FAST_IPSEC)
1589 case IP_IPSEC_POLICY:
1590 {
1591 struct mbuf *m = NULL;
1592 caddr_t req = NULL;
1593 size_t len = 0;
1594
1595 if (m != NULL) {
1596 req = mtod(m, caddr_t);
1597 len = m->m_len;
1598 }
1599 error = ipsec4_get_policy(so->so_pcb, req, len, &m);
1600 if (error == 0)
1601 error = soopt_from_mbuf(sopt, m); /* XXX */
1602 if (error == 0)
1603 m_freem(m);
1604 break;
1605 }
1606 #endif /*IPSEC*/
1607
1608 default:
1609 error = ENOPROTOOPT;
1610 break;
1611 }
1612 break;
1613 }
1614 done:
1615 lwkt_replymsg(&msg->lmsg, error);
1616 }
1617
1618 /*
1619 * Set up IP options in pcb for insertion in output packets.
1620 * Store in mbuf with pointer in pcbopt, adding pseudo-option
1621 * with destination address if source routed.
1622 */
1623 static int
1624 ip_pcbopts(int optname, struct mbuf **pcbopt, struct mbuf *m)
1625 {
1626 int cnt, optlen;
1627 u_char *cp;
1628 u_char opt;
1629
1630 /* turn off any old options */
1631 if (*pcbopt)
1632 m_free(*pcbopt);
1633 *pcbopt = NULL;
1634 if (m == NULL || m->m_len == 0) {
1635 /*
1636 * Only turning off any previous options.
1637 */
1638 if (m != NULL)
1639 m_free(m);
1640 return (0);
1641 }
1642
1643 if (m->m_len % sizeof(int32_t))
1644 goto bad;
1645 /*
1646 * IP first-hop destination address will be stored before
1647 * actual options; move other options back
1648 * and clear it when none present.
1649 */
1650 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN])
1651 goto bad;
1652 cnt = m->m_len;
1653 m->m_len += sizeof(struct in_addr);
1654 cp = mtod(m, u_char *) + sizeof(struct in_addr);
1655 ovbcopy(mtod(m, caddr_t), cp, cnt);
1656 bzero(mtod(m, caddr_t), sizeof(struct in_addr));
1657
1658 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1659 opt = cp[IPOPT_OPTVAL];
1660 if (opt == IPOPT_EOL)
1661 break;
1662 if (opt == IPOPT_NOP)
1663 optlen = 1;
1664 else {
1665 if (cnt < IPOPT_OLEN + sizeof *cp)
1666 goto bad;
1667 optlen = cp[IPOPT_OLEN];
1668 if (optlen < IPOPT_OLEN + sizeof *cp || optlen > cnt)
1669 goto bad;
1670 }
1671 switch (opt) {
1672
1673 default:
1674 break;
1675
1676 case IPOPT_LSRR:
1677 case IPOPT_SSRR:
1678 /*
1679 * user process specifies route as:
1680 * ->A->B->C->D
1681 * D must be our final destination (but we can't
1682 * check that since we may not have connected yet).
1683 * A is first hop destination, which doesn't appear in
1684 * actual IP option, but is stored before the options.
1685 */
1686 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr))
1687 goto bad;
1688 m->m_len -= sizeof(struct in_addr);
1689 cnt -= sizeof(struct in_addr);
1690 optlen -= sizeof(struct in_addr);
1691 cp[IPOPT_OLEN] = optlen;
1692 /*
1693 * Move first hop before start of options.
1694 */
1695 bcopy(&cp[IPOPT_OFFSET+1], mtod(m, caddr_t),
1696 sizeof(struct in_addr));
1697 /*
1698 * Then copy rest of options back
1699 * to close up the deleted entry.
1700 */
1701 ovbcopy(&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr),
1702 &cp[IPOPT_OFFSET+1],
1703 cnt - (IPOPT_MINOFF - 1));
1704 break;
1705 }
1706 }
1707 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr))
1708 goto bad;
1709 *pcbopt = m;
1710 return (0);
1711
1712 bad:
1713 m_free(m);
1714 return (EINVAL);
1715 }
1716
1717 /*
1718 * XXX
1719 * The whole multicast option thing needs to be re-thought.
1720 * Several of these options are equally applicable to non-multicast
1721 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a
1722 * standard option (IP_TTL).
1723 */
1724
1725 /*
1726 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index.
1727 */
1728 static struct ifnet *
1729 ip_multicast_if(struct in_addr *a, int *ifindexp)
1730 {
1731 int ifindex;
1732 struct ifnet *ifp;
1733
1734 if (ifindexp)
1735 *ifindexp = 0;
1736 if (ntohl(a->s_addr) >> 24 == 0) {
1737 ifindex = ntohl(a->s_addr) & 0xffffff;
1738 if (ifindex < 0 || if_index < ifindex)
1739 return NULL;
1740 ifp = ifindex2ifnet[ifindex];
1741 if (ifindexp)
1742 *ifindexp = ifindex;
1743 } else {
1744 ifp = INADDR_TO_IFP(a);
1745 }
1746 return ifp;
1747 }
1748
1749 /*
1750 * Set the IP multicast options in response to user setsockopt().
1751 */
1752 static int
1753 ip_setmoptions(struct sockopt *sopt, struct ip_moptions **imop)
1754 {
1755 int error = 0;
1756 int i;
1757 struct in_addr addr;
1758 struct ip_mreq mreq;
1759 struct ifnet *ifp;
1760 struct ip_moptions *imo = *imop;
1761 int ifindex;
1762
1763 if (imo == NULL) {
1764 /*
1765 * No multicast option buffer attached to the pcb;
1766 * allocate one and initialize to default values.
1767 */
1768 imo = kmalloc(sizeof *imo, M_IPMOPTS, M_WAITOK);
1769
1770 *imop = imo;
1771 imo->imo_multicast_ifp = NULL;
1772 imo->imo_multicast_addr.s_addr = INADDR_ANY;
1773 imo->imo_multicast_vif = -1;
1774 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL;
1775 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP;
1776 imo->imo_num_memberships = 0;
1777 }
1778 switch (sopt->sopt_name) {
1779 /* store an index number for the vif you wanna use in the send */
1780 case IP_MULTICAST_VIF:
1781 if (legal_vif_num == 0) {
1782 error = EOPNOTSUPP;
1783 break;
1784 }
1785 error = soopt_to_kbuf(sopt, &i, sizeof i, sizeof i);
1786 if (error)
1787 break;
1788 if (!legal_vif_num(i) && (i != -1)) {
1789 error = EINVAL;
1790 break;
1791 }
1792 imo->imo_multicast_vif = i;
1793 break;
1794
1795 case IP_MULTICAST_IF:
1796 /*
1797 * Select the interface for outgoing multicast packets.
1798 */
1799 error = soopt_to_kbuf(sopt, &addr, sizeof addr, sizeof addr);
1800 if (error)
1801 break;
1802
1803 /*
1804 * INADDR_ANY is used to remove a previous selection.
1805 * When no interface is selected, a default one is
1806 * chosen every time a multicast packet is sent.
1807 */
1808 if (addr.s_addr == INADDR_ANY) {
1809 imo->imo_multicast_ifp = NULL;
1810 break;
1811 }
1812 /*
1813 * The selected interface is identified by its local
1814 * IP address. Find the interface and confirm that
1815 * it supports multicasting.
1816 */
1817 crit_enter();
1818 ifp = ip_multicast_if(&addr, &ifindex);
1819 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) {
1820 crit_exit();
1821 error = EADDRNOTAVAIL;
1822 break;
1823 }
1824 imo->imo_multicast_ifp = ifp;
1825 if (ifindex)
1826 imo->imo_multicast_addr = addr;
1827 else
1828 imo->imo_multicast_addr.s_addr = INADDR_ANY;
1829 crit_exit();
1830 break;
1831
1832 case IP_MULTICAST_TTL:
1833 /*
1834 * Set the IP time-to-live for outgoing multicast packets.
1835 * The original multicast API required a char argument,
1836 * which is inconsistent with the rest of the socket API.
1837 * We allow either a char or an int.
1838 */
1839 if (sopt->sopt_valsize == 1) {
1840 u_char ttl;
1841 error = soopt_to_kbuf(sopt, &ttl, 1, 1);
1842 if (error)
1843 break;
1844 imo->imo_multicast_ttl = ttl;
1845 } else {
1846 u_int ttl;
1847 error = soopt_to_kbuf(sopt, &ttl, sizeof ttl, sizeof ttl);
1848 if (error)
1849 break;
1850 if (ttl > 255)
1851 error = EINVAL;
1852 else
1853 imo->imo_multicast_ttl = ttl;
1854 }
1855 break;
1856
1857 case IP_MULTICAST_LOOP:
1858 /*
1859 * Set the loopback flag for outgoing multicast packets.
1860 * Must be zero or one. The original multicast API required a
1861 * char argument, which is inconsistent with the rest
1862 * of the socket API. We allow either a char or an int.
1863 */
1864 if (sopt->sopt_valsize == 1) {
1865 u_char loop;
1866
1867 error = soopt_to_kbuf(sopt, &loop, 1, 1);
1868 if (error)
1869 break;
1870 imo->imo_multicast_loop = !!loop;
1871 } else {
1872 u_int loop;
1873
1874 error = soopt_to_kbuf(sopt, &loop, sizeof loop,
1875 sizeof loop);
1876 if (error)
1877 break;
1878 imo->imo_multicast_loop = !!loop;
1879 }
1880 break;
1881
1882 case IP_ADD_MEMBERSHIP:
1883 /*
1884 * Add a multicast group membership.
1885 * Group must be a valid IP multicast address.
1886 */
1887 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq);
1888 if (error)
1889 break;
1890
1891 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
1892 error = EINVAL;
1893 break;
1894 }
1895 crit_enter();
1896 /*
1897 * If no interface address was provided, use the interface of
1898 * the route to the given multicast address.
1899 */
1900 if (mreq.imr_interface.s_addr == INADDR_ANY) {
1901 struct sockaddr_in dst;
1902 struct rtentry *rt;
1903
1904 bzero(&dst, sizeof(struct sockaddr_in));
1905 dst.sin_len = sizeof(struct sockaddr_in);
1906 dst.sin_family = AF_INET;
1907 dst.sin_addr = mreq.imr_multiaddr;
1908 rt = rtlookup((struct sockaddr *)&dst);
1909 if (rt == NULL) {
1910 error = EADDRNOTAVAIL;
1911 crit_exit();
1912 break;
1913 }
1914 --rt->rt_refcnt;
1915 ifp = rt->rt_ifp;
1916 } else {
1917 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
1918 }
1919
1920 /*
1921 * See if we found an interface, and confirm that it
1922 * supports multicast.
1923 */
1924 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) {
1925 error = EADDRNOTAVAIL;
1926 crit_exit();
1927 break;
1928 }
1929 /*
1930 * See if the membership already exists or if all the
1931 * membership slots are full.
1932 */
1933 for (i = 0; i < imo->imo_num_memberships; ++i) {
1934 if (imo->imo_membership[i]->inm_ifp == ifp &&
1935 imo->imo_membership[i]->inm_addr.s_addr
1936 == mreq.imr_multiaddr.s_addr)
1937 break;
1938 }
1939 if (i < imo->imo_num_memberships) {
1940 error = EADDRINUSE;
1941 crit_exit();
1942 break;
1943 }
1944 if (i == IP_MAX_MEMBERSHIPS) {
1945 error = ETOOMANYREFS;
1946 crit_exit();
1947 break;
1948 }
1949 /*
1950 * Everything looks good; add a new record to the multicast
1951 * address list for the given interface.
1952 */
1953 if ((imo->imo_membership[i] =
1954 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) {
1955 error = ENOBUFS;
1956 crit_exit();
1957 break;
1958 }
1959 ++imo->imo_num_memberships;
1960 crit_exit();
1961 break;
1962
1963 case IP_DROP_MEMBERSHIP:
1964 /*
1965 * Drop a multicast group membership.
1966 * Group must be a valid IP multicast address.
1967 */
1968 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq);
1969 if (error)
1970 break;
1971
1972 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
1973 error = EINVAL;
1974 break;
1975 }
1976
1977 crit_enter();
1978 /*
1979 * If an interface address was specified, get a pointer
1980 * to its ifnet structure.
1981 */
1982 if (mreq.imr_interface.s_addr == INADDR_ANY)
1983 ifp = NULL;
1984 else {
1985 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
1986 if (ifp == NULL) {
1987 error = EADDRNOTAVAIL;
1988 crit_exit();
1989 break;
1990 }
1991 }
1992 /*
1993 * Find the membership in the membership array.
1994 */
1995 for (i = 0; i < imo->imo_num_memberships; ++i) {
1996 if ((ifp == NULL ||
1997 imo->imo_membership[i]->inm_ifp == ifp) &&
1998 imo->imo_membership[i]->inm_addr.s_addr ==
1999 mreq.imr_multiaddr.s_addr)
2000 break;
2001 }
2002 if (i == imo->imo_num_memberships) {
2003 error = EADDRNOTAVAIL;
2004 crit_exit();
2005 break;
2006 }
2007 /*
2008 * Give up the multicast address record to which the
2009 * membership points.
2010 */
2011 in_delmulti(imo->imo_membership[i]);
2012 /*
2013 * Remove the gap in the membership array.
2014 */
2015 for (++i; i < imo->imo_num_memberships; ++i)
2016 imo->imo_membership[i-1] = imo->imo_membership[i];
2017 --imo->imo_num_memberships;
2018 crit_exit();
2019 break;
2020
2021 default:
2022 error = EOPNOTSUPP;
2023 break;
2024 }
2025
2026 /*
2027 * If all options have default values, no need to keep the mbuf.
2028 */
2029 if (imo->imo_multicast_ifp == NULL &&
2030 imo->imo_multicast_vif == -1 &&
2031 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL &&
2032 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP &&
2033 imo->imo_num_memberships == 0) {
2034 kfree(*imop, M_IPMOPTS);
2035 *imop = NULL;
2036 }
2037
2038 return (error);
2039 }
2040
2041 /*
2042 * Return the IP multicast options in response to user getsockopt().
2043 */
2044 static int
2045 ip_getmoptions(struct sockopt *sopt, struct ip_moptions *imo)
2046 {
2047 struct in_addr addr;
2048 struct in_ifaddr *ia;
2049 int error, optval;
2050 u_char coptval;
2051
2052 error = 0;
2053 switch (sopt->sopt_name) {
2054 case IP_MULTICAST_VIF:
2055 if (imo != NULL)
2056 optval = imo->imo_multicast_vif;
2057 else
2058 optval = -1;
2059 soopt_from_kbuf(sopt, &optval, sizeof optval);
2060 break;
2061
2062 case IP_MULTICAST_IF:
2063 if (imo == NULL || imo->imo_multicast_ifp == NULL)
2064 addr.s_addr = INADDR_ANY;
2065 else if (imo->imo_multicast_addr.s_addr) {
2066 /* return the value user has set */
2067 addr = imo->imo_multicast_addr;
2068 } else {
2069 ia = IFP_TO_IA(imo->imo_multicast_ifp);
2070 addr.s_addr = (ia == NULL) ? INADDR_ANY
2071 : IA_SIN(ia)->sin_addr.s_addr;
2072 }
2073 soopt_from_kbuf(sopt, &addr, sizeof addr);
2074 break;
2075
2076 case IP_MULTICAST_TTL:
2077 if (imo == NULL)
2078 optval = coptval = IP_DEFAULT_MULTICAST_TTL;
2079 else
2080 optval = coptval = imo->imo_multicast_ttl;
2081 if (sopt->sopt_valsize == 1)
2082 soopt_from_kbuf(sopt, &coptval, 1);
2083 else
2084 soopt_from_kbuf(sopt, &optval, sizeof optval);
2085 break;
2086
2087 case IP_MULTICAST_LOOP:
2088 if (imo == NULL)
2089 optval = coptval = IP_DEFAULT_MULTICAST_LOOP;
2090 else
2091 optval = coptval = imo->imo_multicast_loop;
2092 if (sopt->sopt_valsize == 1)
2093 soopt_from_kbuf(sopt, &coptval, 1);
2094 else
2095 soopt_from_kbuf(sopt, &optval, sizeof optval);
2096 break;
2097
2098 default:
2099 error = ENOPROTOOPT;
2100 break;
2101 }
2102 return (error);
2103 }
2104
2105 /*
2106 * Discard the IP multicast options.
2107 */
2108 void
2109 ip_freemoptions(struct ip_moptions *imo)
2110 {
2111 int i;
2112
2113 if (imo != NULL) {
2114 for (i = 0; i < imo->imo_num_memberships; ++i)
2115 in_delmulti(imo->imo_membership[i]);
2116 kfree(imo, M_IPMOPTS);
2117 }
2118 }
2119
2120 /*
2121 * Routine called from ip_output() to loop back a copy of an IP multicast
2122 * packet to the input queue of a specified interface. Note that this
2123 * calls the output routine of the loopback "driver", but with an interface
2124 * pointer that might NOT be a loopback interface -- evil, but easier than
2125 * replicating that code here.
2126 */
2127 static void
2128 ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst,
2129 int hlen)
2130 {
2131 struct ip *ip;
2132 struct mbuf *copym;
2133
2134 copym = m_copypacket(m, MB_DONTWAIT);
2135 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen))
2136 copym = m_pullup(copym, hlen);
2137 if (copym != NULL) {
2138 /*
2139 * if the checksum hasn't been computed, mark it as valid
2140 */
2141 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
2142 in_delayed_cksum(copym);
2143 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
2144 copym->m_pkthdr.csum_flags |=
2145 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
2146 copym->m_pkthdr.csum_data = 0xffff;
2147 }
2148 /*
2149 * We don't bother to fragment if the IP length is greater
2150 * than the interface's MTU. Can this possibly matter?
2151 */
2152 ip = mtod(copym, struct ip *);
2153 ip->ip_len = htons(ip->ip_len);
2154 ip->ip_off = htons(ip->ip_off);
2155 ip->ip_sum = 0;
2156 if (ip->ip_vhl == IP_VHL_BORING) {
2157 ip->ip_sum = in_cksum_hdr(ip);
2158 } else {
2159 ip->ip_sum = in_cksum(copym, hlen);
2160 }
2161 /*
2162 * NB:
2163 * It's not clear whether there are any lingering
2164 * reentrancy problems in other areas which might
2165 * be exposed by using ip_input directly (in
2166 * particular, everything which modifies the packet
2167 * in-place). Yet another option is using the
2168 * protosw directly to deliver the looped back
2169 * packet. For the moment, we'll err on the side
2170 * of safety by using if_simloop().
2171 */
2172 #if 1 /* XXX */
2173 if (dst->sin_family != AF_INET) {
2174 kprintf("ip_mloopback: bad address family %d\n",
2175 dst->sin_family);
2176 dst->sin_family = AF_INET;
2177 }
2178 #endif
2179 get_mplock(); /* is if_simloop() mpsafe yet? */
2180 if_simloop(ifp, copym, dst->sin_family, 0);
2181 rel_mplock();
2182 }
2183 }
DragonFly BSD